structure of human genome Flashcards
What is a nucleosome
A protein DNA complex.
Dna coiled around a core of histones
What does Giemsa stain do?
Stains metaphase chromosomes
What is karyotyping
The process of pairing and ordering all the chromosomes of an organisms which provides a genome (wide snapshot of an individual’s chromosomes).
Old method to check if one has the right number of chromosomes
What is a genome?
Sum total of all genetic information in an organisms
What have mitochondria evolved from?
Derived from a-proteobacteria
What is a-proteobacteria
Class of Gram-negative bacteria known for metabolic diversity and ecological roles such as nitrogen fixation, symbiosis with plants, and organic compound degradation.
What organism are chloroplasts derived from?
Cyanobacteria
How many membranes around nucleus?
2
What is a nucleolus and what does it do?
Dense part of the nucleus.
Site of ribosome synthesis
What are chromosome territories?
A particular chromosome has an area of probable distribution in the cell.
Where would a chromosome more likely to be located if it had more activity (more gene rich)?
Found towards interior of the nucleus
What is an “open” and “closed” chromatin?
Closed (heterochromatin) - doesn’t have many genes because it’s more of a structural role, not typically transcribed. Compact.
Open (Euchromatin) - Gene rich chromatin. More relaxed and often transcribed.
What determines the eu or heterochromatic state?
Where does histone modification primarily take place?
On the histone tails
What are three histone modifications?
Acetylation: Modifies K-ac. Regulates transcription, repair, replication, condensation
Methylation (lysines): Modifies K-mel, K-me2, K-me3. Regulates Transcription and repair
Methylation: Modifies R-mel, R-me2a, R-me2s. Regulates Transcription
Phosphorylation: Modifies S-ph, T-ph. Regulates Transcription, Repair, Condensation
